xxx B. Kulishov, D. Minkin, A. Fedorov and A. Novoselov
Development of the mathematical model of the electric resistance baking process
Abstract |

# Development of the mathematical model of the electric resistance baking process

B. Kulishov¹*, D. Minkin², A. Fedorov¹ and A. Novoselov¹

¹ITMO University, Saint Petersburg, Faculty of Food Biotechnologies and Engineering, School of Biotechnology and Cryogenic Systems, Kronverkskiy ave.49, RU197101 St. Petersburg, Russia
²Saint Petersburg University of State Fire Service of Emercom of Russia, Department of Physical and Technical Fundamentals of Fire Safety, Moskovskiy ave.149, RU 196105 St. Petersburg, Russia
*Correspondence: kulishov.b@list.ru

### Abstract:

The work is dedicated to the development of the mathematical model of the electric resistance baking process for the purpose of predicting temperature changes during baking of dough pieces of arbitrary sizes. The equation for the non-stationary thermal regime of a body with an internal heat source was used with a number of assumptions. The dynamics of the dough temperature changes was determined by numerical solution of the equation in Comsol Multiphysics.
Due to the complexity of the dough baking process and the impossibility of solving the equation by analytical method only, a number of values included in the energy balance of ER baking were determined experimentally. A dough piece with dimensions of 100×50×80 mm was baked during the experiment. After the adjustment, the adequacy of the model was checked by comparing the data on the dough temperature changes during baking dough pieces of the same recipe, but of different sizes (150×49×80, 80×62×80, and 65×75×80). Statistical analysis using Fisher’s criterion confirmed the adequacy of the model.

### Key words:

2449-2464 B. Kulishov, K. Kulishova, N. Rudometova, A. Fedorov and A. Novoselov
Advantages of electric resistance method for baking bread and flour confectionery products of functional purpose
Abstract |

# Advantages of electric resistance method for baking bread and flour confectionery products of functional purpose

B. Kulishov¹*, K. Kulishova¹², N. Rudometova¹², A. Fedorov¹ and A. Novoselov¹

¹ITMO University, Saint-Petersburg, Faculty of Food Biotechnologies and Engineering, School of Biotechnology and Cryogenic Systems, Kronverkskiy ave. 49, RU 197101 St. Petersburg, Russia
²All-Russian Research Institute for Food Additives – Branch of V.M. Gorbatov Federal Research Center for Food Systems of RAS, Liteyniy ave. 55, RU 191014 St. Petersburg, Russia
*Correspondence: kulishov.b@list.ru

### Abstract:

In this paper we studied the effect of the baking method on the preservation of beta-carotene in two types of products: pan wheat bread and sponge cake. Five sources of beta-carotene were used in the study, three of which are commercially available samples, and the two others are experimental samples of supramolecular complexes of beta-carotene with alpha- and beta-cyclodextrins in powder form (molecular ratio 1: 1). Bread and sponge cake were baked by convective and electric resistance methods. The values of temperature and current flowing through the dough were monitored during electric resistance baking. The beta-carotene content was measured in the dough after kneading, in the cake batter after mixing and in the finished products after baking and cooling. The beta-carotene content was evaluated by spectrophotometry after extraction. The control samples of bread and sponge cake were baked without adding beta-carotene. Different sources of beta-carotene exhibited varying stability in bread and sponge cake. Bread samples baked by the electric resistance method with addition of supramolecular complexes had minimum losses of beta-carotene. Electric resistance baking ensured lower losses of beta-carotene in bread and sponge cake samples.

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1873–1887 O. Savkina, L. Kuznetsova, M. Burykina, M. Kostyuchenko and O. Parakhina
The influence of the flour amylolytic enzymes activity, dosage of ingredients and bread making method on the sugar content and the bread quality
Abstract |

# The influence of the flour amylolytic enzymes activity, dosage of ingredients and bread making method on the sugar content and the bread quality

O. Savkina¹*, L. Kuznetsova¹, M. Burykina¹, M. Kostyuchenko² and O. Parakhina¹

¹St.Petersburg branch State Research Institute of Baking Industry, Podbelskogo highway 7, RU196608, St. Petersburg, Pushkin, Russia
²State Research Institute of Baking Industry, Bolshaya Cherkizovskaya street 26A, RU107553, Moscow, Russia
*Correspondence: 1103savkina@mail.ru

### Key words:

1299–1312 N. Dubrovskaya, O. Savkina, L. Kuznetsova, O. Parakhina and L. Usova
Accelerated technology of rye bread with improved quality and increased nutritional value
Abstract |

# Accelerated technology of rye bread with improved quality and increased nutritional value

N. Dubrovskaya¹*, O. Savkina², L. Kuznetsova³, O. Parakhina² and L. Usova²

¹Peter the Great St. Petersburg Polytechnic University, Polytechnicheskaya, 29, RU195251 St. Petersburg, Russia
²St. Petersburg branch State Research Institute of Baking Industry, Podbelskogo highway 7, RU196608 St. Petersburg, Pushkin, Russia
³Institute of Refrigeration and Biotechnologies, ITMO University, Lomonosova street, 9, RU191002 St. Petersburg, Russia
*Correspondence: dubrovskaja_nata@mail.ru

### Key words:

1375–1385 N. Naumenko, A. Paymulina, A. Ruskina, V. Khudyakov
The Effects of Various Raw Ingredients on Bread Quality
Abstract |

# The Effects of Various Raw Ingredients on Bread Quality

N. Naumenko,* A. Paymulina, A. Ruskina, V. Khudyakov

South Ural State University, Higher School of Medicine and Biology, Department of
Food and Biotechnology, 85 Lenina Avenue, 454080 Chelyabinsk, Russia;
*Correspondence: naumenko_natalya@mail.ru

### Abstract:

The purpose of the current research is to study the mechanisms behind how various
raw ingredients affect the quality of bread. The objects of the research were the flour used in
making the bread (consisting of gluten at 28.5%, and with an ash content of 0.55), with no added
fats; tap water or activated water (treated in a USTA-0.4/22 OM ultrasonic processor (Volna,
Russia), operating at a frequency of 22±1.65kHz and at 30% of maximum output power (400W)
for mixing dough); and plant extract additives based on stevioside and fucoidan (fully replacing
the sugar). Included in the analysis were the effects of using activated water and combined plant
extract additives on organoleptic qualities (appearance, crust colour, crumb condition, taste,
stickiness during mastication, and friability), as well as the physical and chemical qualities
(moisture content, porosity, and acidity). Yeast activity was studied in dough which had been
produced using activated water and combined plant extract additives. An Altami-136T optical
microscope (Altami, Russia) was used to study the activity of yeast cells. The effects of activated
water and combined plant extract additives were analysed by examining the microstructure.
Microscopic studies were carried out using a Jeol JEM-2100 electron microscope (Jeol Ltd,
Japan). The results confirm that activated water and combined plant extract additives may be used
to improve the quality of fresh bread.

### Key words:

1386–1398 L. Nilova, N. Naumenko, I. Kalinina
A Study of the Forms of Bound Water in Bread and Bakery Products using Differential Thermal Analysis
Abstract |

# A Study of the Forms of Bound Water in Bread and Bakery Products using Differential Thermal Analysis

L. Nilova¹, N. Naumenko²*, I. Kalinina²

¹Peter the Great St. Petersburg Polytechnic University, Institute of Industrial Management, Economics and Trade, Graduate School of Commodity and Service, Novorossiyskaya Street 50, 194021, Saint-Petersburg, Russia;
²South Ural State University, Higher School of Medicine and Biology, Department of Food and Biotechnology, 85 Lenina Avenue, 454080, Chelyabinsk, Russia;
* Correspondence: naumenko_natalya@mail.ru

### Abstract:

The objective is to study the forms of bound water in bread and bakery products using differential thermal analysis, changes to these forms corresponding to different recipe components, and changes occurring during storage. The subject of this research are bread and bakery products made of wheat flour (with gluten content of 28.5%, and ash content of 0.55%): without added fat; with tap water or activated water used for dough mixing; with varying fat content (4 and 14%); protein-enriched with cedar nut flour (5%); and dietary (food) fiberenriched with red-fruited mountain ash and sea buckthorn powder (5%). The reference samples of bread and bakery products were stored in plastic film bags at 20 ± 2 °C for a period of 72 hours. The freshness was monitored by changes in the physical-chemical parameters (moisture content, swelling capacity, friability). The various forms of bound water were determined using the method of differential thermal analysis on a simultaneous TGA-DTA/DSC thermogravimetric analyzer, with a programmable temperature regime. Based on the obtained digital data on thermogram (TG) change, using Pearson’s criterion, a mathematical model has been created to identify the linear sections with a different inclination angle which are characterized by a constant rate of water removal. For all studied samples of bakery products, 6 linear sections were identified, but statistically significant results were obtained for sections III, IV and V, with the exception of section III for bakery products with cedar flour. Use of activated water, fat, and additives of cedar flour, powders of red-fruited mountain ash and seabuckthorn in the production of bread and bakery products leads to redistribution of water forms, which is confirmed by changes in the boundaries of the linear sections, both for freshly made products and for products after storage. As a result, these products stay fresh longer.

### Key words:

1348–1357 L. Kuznetsova & O. Savkina
A study of factors which influence mould spoilage in flat (sourdough) bread
Abstract |

# A study of factors which influence mould spoilage in flat (sourdough) bread

L. Kuznetsova & O. Savkina*

Institute of Refrigeration and Biotechnologies, ITMO University, Lomonosova Street 9, 191002 St Petersburg, Russia;
*Correspondence: 1103savkina@mail.ru

### Abstract:

Bakery products are an excellent substrate for the development of microbial spoilage, especially mould spoilage and lime disease (otherwise known as chalk disease), because they have high levels of water activity aw = 0.94-0.97 and pH 5.5-6.0. Sliced bread in its packaging is highly susceptible to moulds and lime disease during storage. The aim of this study was to investigate the effects shown by the microbial contamination of flour quality, and the type of sourdough and organic acid, especially acetic acid, on mould spoilage in wheat and rye wheat bread. Microbial contaminations were studied in two batches of wheat flour and three batches of rye flour which had been manufactured in Belarus and Russia and in sourdough bread which had been produced using this flour. Investigated here was the impact of the quality and type of sourdough with various starter cultures of micro-organisms and the impact of the content of organic acid, especially acetic acid, on mould spoilage in wheat and rye wheat bread. The content of organic acids, including acetic acid, in different types of sourdough which has been prepared using different starter cultures and in different kinds of sourdough bread which have been studied using liquid chromatography. It was found that, in spite of the presence in flour of spore-forming bacteria, yeasts, and fungi, microbial contamination of the finished product immediately after baking was absent. It was proven that the use of starter cultures and sourdough can slow down or prevent entirely the microbial spoilage of bread. It was found that the content of acetic acid which had been accumulated during the fermentation of various types of sourdough served to effect the presence of mould spoilage on sourdough bread.